Multi-Criteria Evaluation Model for Desertification Hazard Zonation mapping Using GIS (Study Area: Trouti Watershed, Golestan, Iran)

Desertification is one of the major issues threatening human communities. Manymethods have been developed for assessment and mapping of desertification hazards. In thisresearch, multi-criteria evaluation method was used to investigate desertification process inTrouti watershed, Golestan Province, Iran. At the first step, major desertification factors weredetermined by doing field surveys. They were soil texture, aspect, rainfall, sensitivity ofgeological formation to erosion, hydrologic soil group, slope and land use. The next step,information layers were digitized in GIS environment and Digitized maps were converted tofuzzy standard maps using fuzzy membership functions in IDRISI software. Then, weight ofeach factor was determined with the contribution of Analytical Hierarchy Process. Finally, thesusceptible areas to desertification in the study area were identified using Multi-criteriaevaluation method. The results showed that 36.55, 15.21, 40.17 and 8.07 % of the study areawere classified as severe, high, moderate and slow affected by desertification, respectively. Itwas concluded that land use and sensitivity of geological formations to erosion were the mostimportant factors affecting desertification process in Trouti watershed of Golestan Province.